In the MMC Console, in the console tree, expand Certificates - Service (Active Directory Domain Services), right-click on NTDS/Personal, and select Import.

In the Certificate Import Wizard, on the Welcome to the Certificate Import page, click Next.

On the File to Import page, click Browse to browse for and select the .pfx certificate file (e.g. your_domain_com.pfx) that you exported using the DigiCert Certificate Utility, select the file, click Open, and then, click Next.

On the Password page, do the following:

In the Password box, enter the password that you created when you exported the .pfx certificate file.

Check Include all extended properties.

Check Mark this key as exportable.

Click Next.

On the Certificate Store page, leave the default settings and click Next.